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authorMichael R Sweet <michael.r.sweet@gmail.com>2004-09-08 16:04:43 +0000
committerMichael R Sweet <michael.r.sweet@gmail.com>2004-09-08 16:04:43 +0000
commit88ff012c446c98bf017a29af883d0d6b0c25c26d (patch)
tree5e16df496a98b33aa9cb875ee5785945943f5034 /zlib/adler32.c
parent53d7e32ff3f2c6baf17d10988736ba6bf3f8c4c6 (diff)
Update PNG to 1.2.6 + wutil patch.
Update ZLIB to 1.2.1. git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@3809 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
Diffstat (limited to 'zlib/adler32.c')
-rw-r--r--zlib/adler32.c44
1 files changed, 35 insertions, 9 deletions
diff --git a/zlib/adler32.c b/zlib/adler32.c
index 2650c2c9b..f225f5465 100644
--- a/zlib/adler32.c
+++ b/zlib/adler32.c
@@ -1,13 +1,14 @@
/* adler32.c -- compute the Adler-32 checksum of a data stream
- * Copyright (C) 1995-2002 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
+ * Copyright (C) 1995-2003 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
*/
-/* @(#) $Id: adler32.c,v 1.1.2.1 2004/07/05 14:12:38 easysw Exp $ */
+/* @(#) $Id: adler32.c,v 1.1.2.2 2004/09/08 16:04:42 easysw Exp $ */
+#define ZLIB_INTERNAL
#include "zlib.h"
-#define BASE 65521L /* largest prime smaller than 65536 */
+#define BASE 65521UL /* largest prime smaller than 65536 */
#define NMAX 5552
/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
@@ -17,6 +18,31 @@
#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
#define DO16(buf) DO8(buf,0); DO8(buf,8);
+#ifdef NO_DIVIDE
+# define MOD(a) \
+ do { \
+ if (a >= (BASE << 16)) a -= (BASE << 16); \
+ if (a >= (BASE << 15)) a -= (BASE << 15); \
+ if (a >= (BASE << 14)) a -= (BASE << 14); \
+ if (a >= (BASE << 13)) a -= (BASE << 13); \
+ if (a >= (BASE << 12)) a -= (BASE << 12); \
+ if (a >= (BASE << 11)) a -= (BASE << 11); \
+ if (a >= (BASE << 10)) a -= (BASE << 10); \
+ if (a >= (BASE << 9)) a -= (BASE << 9); \
+ if (a >= (BASE << 8)) a -= (BASE << 8); \
+ if (a >= (BASE << 7)) a -= (BASE << 7); \
+ if (a >= (BASE << 6)) a -= (BASE << 6); \
+ if (a >= (BASE << 5)) a -= (BASE << 5); \
+ if (a >= (BASE << 4)) a -= (BASE << 4); \
+ if (a >= (BASE << 3)) a -= (BASE << 3); \
+ if (a >= (BASE << 2)) a -= (BASE << 2); \
+ if (a >= (BASE << 1)) a -= (BASE << 1); \
+ if (a >= BASE) a -= BASE; \
+ } while (0)
+#else
+# define MOD(a) a %= BASE
+#endif
+
/* ========================================================================= */
uLong ZEXPORT adler32(adler, buf, len)
uLong adler;
@@ -30,19 +56,19 @@ uLong ZEXPORT adler32(adler, buf, len)
if (buf == Z_NULL) return 1L;
while (len > 0) {
- k = len < NMAX ? len : NMAX;
+ k = len < NMAX ? (int)len : NMAX;
len -= k;
while (k >= 16) {
DO16(buf);
- buf += 16;
+ buf += 16;
k -= 16;
}
if (k != 0) do {
s1 += *buf++;
- s2 += s1;
+ s2 += s1;
} while (--k);
- s1 %= BASE;
- s2 %= BASE;
+ MOD(s1);
+ MOD(s2);
}
return (s2 << 16) | s1;
}